Women have been required to wear at least a hijab while in public since the country's Islamic revolution of 1979. In recent years prosecutors have shown "tolerance" to women who wear theirs loosely, but Mr Dolatabadi said authorities will no longer accept deliberate flouting of the rules.

"We must act with force against people who deliberately question the rules on the Islamic veil," he said, according to local reports.

The woman is reportedly appealing the sentence. She will be eligible for parole after three months.